CRANIAL CT REVISITED - DO WE REALLY NEED CONTRAST ENHANCEMENT

The aim of this study was to define guidelines for intravenous contras t administration in cranial CT, as currently there are no recent guide lines based on a large series of patients. In 1900 consecutive patient s (1480 adults and 420 children) pre- and post-contrast scan was analy sed in order to assess the contribution of contrast enhancement to the diagnosis. The findings were grouped according to whether abnormaliti es were seen on the pre- and/or post-contrast scan, or whether no abno rmalities were seen at all. Sensitivity, specificity, positive predict ive value, negative predictive value and accuracy of a pre-contrast sc an were used to determine validity. Intravenous contrast enhancement o nly contributes to the diagnosis if a suspicious abnormality is seen o n the unenhanced scan or int he appropriate clinical setting (33.6%). In the remaining patients (65.6%) there is no diagnostic contribution, except for a small number of abnormalities (0.8%). These are often an atomical variants and have no therapeutic impact. The number of contra st-enhanced cranial CT examinations can significantly be reduced by us ing four general guidelines for contrast administration resulting in c onsiderable cost savings without affecting the quality of service to t he patient. These guidelines are defined by the clinical findings/pres entation or by the findings on the unenhanced scan. The number of cont rast-related complications will be reduced, which may have medicolegal implications. These guidelines can be applied in any radiology depart ment.